Variable-speed driving mechanism.



N0. 807,216. PATENTED DEC. 12, 1905'.

R. STOGKBRIDGE.

VARIABLE SPEED DRIVING MECHANISM. APPLIOATION rump 1130.9, 1903.

. (M InUen- L or \A/finesses R df q or'd Sioc bruiga f Qj UNTTED STATES PATENT OFFICE.

RADFORD STOCKBRIDGE, OF l/VORCESTER, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO ARTHUR W. BEAMAN, OF WORCESTER, MASSA- CHUSETTS.

VARIABLE-SPEED DRIVING MECHANISM.

Specification of Letters Patent.

Patented Dec. 12, 1905.

Original application filed October 24,1902, Serial No.128.552. Divided and this application filed December 9, 1903. Serial No. 184,393.

drawings forming a part of the same and representing my variable-speed mechanism as applied to a shapmg-machme, in which Figure 1 1s a top view of a variable pitman with its actuating mechanism. Fig. 2 represents the variable pitman with its actuating mechanism shown in central vertical sectional View. Fig. 3 is a view of the actuating mechanism for driving the variable pitman, the pitman having been removed. Fig. 4 represents a portion of the mechanism for driving the variable pitman, the crank-plate having been removed to disclose the eccentric; and Fig. 5 represents the mechanism for driving the variable pitman, showing the side opposite that shown in Fig. 3.

Similar reference-figures refer to similar parts in the different views. My invention has for its object to provide an improved mechanism for driving the variable pitman by which a reciprocating movement is given to the ram carrying the cuttingtool; and it consists in the construction and arrangement of parts, as hereinafter described, and set forth in the annexed claims.

This application is a division of my pending application, filed October 24, 1902, Serial N 0. 128,552.

In the accompanying drawings, 1 denotes the supporting-framework, provided at the top with horizontal ways 2 for a reciprocating ram 3, provided at one end with a head 4, adapted to carry a cutting-tool, these parts being substantially the same as in machines of this class now in common use.

Power is applied to the machine by means of a cone-pulley 5, carried upon a shaft 6, to the inner end of which a pinion 7 is attached, (shown in Fig. 2,) which engages a gear 8, provided with a hub 9, which rotates on the outside of a fixed hub 10, which is provided with a flange '11, by which it is attached to the framework of the machine. Rigidly attached to the inside of the hub 10 is an cecentric 12, having an eccentric-ring 13, which is rotated around the fixed eccentric bymeans of a sliding block 14, carried by the gear 8 and capable of a radial sliding motion in ways on the side of the gear 8 and pivotally connected with the eccentric-ring by a stud 14 The eccentric-ring carries a stud 16, upon which is pivotally mounted a sliding block 17, capable of a radial sliding movement in a radial slot 18 in a crank-plate 19, provided with a long hub 20, which is journaled inside the fixed hub 10. The crank-plate 19 is also provided with radial ways 21, in which is held a block 22 and radially adjustable therein by means of adj usting-screws 23, which is rotated by the attendant by means of a spindle 24, ournaled concentrically with the rotating crankplate 19 and provided with a squared end 25, Fig. 2, to receive a wrench. The spindle 24 is' connected by intermediate gearing 26 with the adj usting-screw 23. The block 22 is provided with a stud 27, on which is pivoted a block 28, capable of slidinginvertical ways 29 29 in a variable pitman 30,

pivoted at its lower end 31 upon a stud in the framework of the machine.

The upper end 33 of the variable pitman carries a friction-roll 34, which engages a slot 35 in a block 36, carried by the reciprocating ram 3.

The operation of the ram-reciprocating mechanism is as follows: Motion is imparted to the gear 8 by the pinion 7, causing it to rotate around the fixed hub 10. The gear 8 rotates around the fixed eccentric 12 and carries the eccentric-ring 13 by means of the radially-sliding block 14, held in the ways 15 of the gear and pivotally connected with the eccentric-ring by the stud 14 As the eccentric-ring is rotated around the fixed eccentric the block 14 will move in and out in the radial ways 15, and thereby impart a variable motion to the eccentric-ring. The rotating eccentric ring drives the crankplate 19 through the stud 16 and block 17, held in the radial slot 18 of the crank-plate, and the rotation of the crank-plate 19 imparts a vibrating movement to the pitman 30 by means of the block 22,'radially adjustable in the ways 21 of the crank-plate,

I stud 27, carried by the block 22 and the block 28, pivoted on the stud 27 and held in the vertical ways 29 of the pitman 30. The gearwheel 8 rotates in the direction of the arrow 37, Fig. 1, and the actuating mechanism in Figs; 1 and 2 are shown in the position assumed when the vibrating pitman is in the middle of its forward stroke, which is the cutting stroke of the machine. During the forward stroke of the pitman the crankblock 28 is moving through the upper half of its circular path and farthest from the pivoted end 31 of the pitman, while upon the reverse movement of the pitman or return stroke the crank-block 28 moves through the lower half of its path and nearest the pivoted end 31 of the pitman. Consequently the ram 3 is retarded during its forward stroke and accelerated during its return stroke independently of the variable movement of the crank-plate. I increase the retardation and acceleration of the pitman, however, by imparting a variable motion to the crank-plate by interposing the eccentric 12 and eccentricring 13 between the crank-plate 19 and the driving-gear 8, thereby imparting a variable motion to the eccentric-ring from the driving gear, from the eccentric-ring to the crank plate 19. A variable motion has heretofore been imparted to the crank-plate in machines of this class by ournaling the crankplate eccentrioally to the axis of its drivinggear and driving the crank-plate by means of a stud carried by the gear and entering a radial slot in the crank-plate. By this method of driving the crank-plate the eccentrioity of the crank-plate is limited, and the stud which is carried by the driving-gear is always at the same radial distance from its axis of rotation.

By my improved construction the eccentric is rotated by a stud carried by the eccen-v tric and enterin a radial slot in the drivinggear, and when t e greatest power is required or during the forward or cutting stroke of the pitman the driving-stud 14 is nearest the axis of the driving-gear 8, and at the same time the driving power is applied to the gear 8 at its periphery by means of the pinion 7, thereby multiplying the power applied during the cutting stroke of the machine. I am also enabled to materially increase the variation in the movement of the pitman, for the reason that the radial ways 15 can extend from the hub of the gear 8 to its periphery,

thereby allowing a corresponding eccen trioity to the fixed eccentric 12.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The combination with a slotted vibrating pitman and a crank-plate engaging the slot of said pitman, said crankplate having a'radial slot, of a rotating gear journaled concentrically with said crank-plate and having a radial slot and a rotating ring interposed between said gear and said crank-plate and having its axis eccentric to the axis of said gear and said crankplate, said eccentric-ring engaging the slots in said crank-plate and said gear, whereby the rotation of said gear is imparted to said crank-plate with a variable movement.

2. The combination with a framework, of a fixed hollow hub, a crank-plate journaled within said hub, a gear journaled outside said hub and concentrically with said crankplate, and an eccentricring interposed between said gear and said crank-plate, radial slots in said gear and said crank-plate, and sliding blocks engaging said slots and pivotally attached to said eccentric-ring.

3. The combination of a rotating gear and a crank-plate journaled concentrically, interposed connecting mechanism between said gear and crank-plate whereby the latter is driving at a variable speed from said gear, a slotted vibrating pitman, a sliding block in the slot of the pitman pivotally attached to a block carried by said crank-plate, and means for radially varying the position of said block, comprising a rotating spindle j ournaled concentrically with said crankplate.

4. The combination with a framework having a fixed hollow hub, of a rotating gear journaled on the outside of said hub, a crankplate journaled inside said hub and concentrically with said gear, an eccentric attached to said hub between said gear and crankplate, a ring turning on said eccentric, means for operatively connecting said gear and said ring, whereby the latter is driven by said gear, and means for operatively connecting said ring and said crank-plate, whereby the latter is driven by said ring.

RADFORD STOOKBRIDGE.

Witnesses:

PENELOPE CoMBERBAoH, RUFUS B. FOWLER. 

